Grain separator chaffer assembly



March 26, 1968 A. s. LIGHTSEY 3,374,886

GRAIN SEPARATOR CHAFFER ASSEMBLY Filed May 2, 1966 '2 SheetsSheet l EraJ 50 o INVENTOR.

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United States Patent Office 3,374,886 Patented Mar. 26, 1968 GRAINSEPARATOR CHAFFER ASSEMBLY Arthur S. Lightsey, Cantua Creek, Calif.

(1280 Allen Ave., Oakdale, Calif. 95361) Continuation-impart ofapplication Ser. No. 346,719, Feb. 24, 1964. This application May 2,1966, Ser. No. 546,914

2 Claims. (Cl. 209-28) ABSTRACT OF THE DISCLOSURE A chaffer assembly forcombines and grain separators formed from corrugated material havingrows of air inlet openings so arranged relative to adjustable airdeflectors as to provide closely spaced sheet-like generally verticalstreams of air flowing upward through the stream of chaff and strawpassing rearwardly over the top of the chaffer assembly. The risingstreams of air do not tend to blow the grain toward the rear end of thechatfer assembly and the relatively quiet air between the verticallyrising air streams allows the grain to fall and pass through the airinlet openings into the grain collecting chamber below the chatferassembly.

This application is a continuation-in-part of my copending applicationfor United States Letters Patent Ser. No. 346,719, filed Feb. 24, 1964,entitled, Grain Separator Chatfer Assembly, and now abandoned.

This invention relates to grain separators and more particularly to animproved chaffer assembly having as its object the provision of asimpler, more rugged, easily controlled device for agitating andlevitating a stream of straw and chaff while passing rearwardlythereacross, and for creating and utilizing rising, spaced-apart sheetsof air extending crosswise of the stream of straw flow to facilitate thegravitation of grain and the escape thereof through the chatferassembly.

As is well known, grain separators include various components in theirforward portions for feeding and butfeting stalks and attached heads ofgrain for the purpose of breaking open the grain-carrying husks.Thereafter, the problem is to separate the free grain from the straw andchaff as the latter is being discharged from the separator in a streamof air. During this final separating operation, the straw is advancedrearwardly over mechanically driven walker devices as the grain, chaffand portions of the straw fall therethrough and are carried rearwardlyover a chaffer assembly under conditions intended to separate the grainfor passage downwardly through the chatfer into collecting chamberstherebelow.

There have been many proposals for chatfer assemblies having variousarrangements for passing jets of air upwardly into the straw and grainto agitate the latter and facilitate the separation of the grain. Manyof these proposals include provision for adjusting the size of the airopenings and the quantity of the air passing upwardly therethrough.However, as is well known to those skilled in this art, these priorconstructions are quite sensitive to a wide range of factors and provideefficient separation under certain operating conditions but highlyunreliable and inefficient separation under slightly differentconditions with the result that excessive portions of the grain are lostand carried away in the straw discharging from the separator.

Accordingly, it is a primary purpose of the present invention to providean improved chatfer assembly to separate grain from straw and chaff andfeaturing provision for a plurality of thin, vertically directed streamsof air extending crosswise of the separator and spaced from one anothersufficiently to provide relatively quiescent air spaces therebetween forthe gravitation of grain downwardly onto imperforate surfaces of thechatfer assembly and through the air inlet openings. These spacedapartrising streams or sheets of air issue upwardly through the chatfer at anacute angle to imperforate wall portions of the chatfer and cooperatewith these walls in creating low pressure areas in these grain flowspaces. Of importance is the fact that these air streams do not pass incontact with the aforementioned imperforate surfaces. In consequence,the air streams are not effective to project the grain over the crestsof the chatfer corrugations toward the separator exit but, on thecontrary, create low pressure areas and a freer path for the downwardgravitation of the grain therealong.

An important feature of the chatfer assembly, according to the presentinvention, is the provision therebelow of air-directing means forguiding the rising streams of air through the chatfer openings and alonga vertical path inclined to the above-mentioned imperforate walls.Desirably, the air-directing means are adjustable to accommodate thechatfer for most efficient use with a wide range of grain sizes andweights. However, it is found that a single setting of the air-directingmeans suffices to handle grain of a wide variety of kinds and sizessince the principal purpose and function of the air-directing means isto avoid having the air streams wipe across and in contact with theimperforate walls of the corrugations, but instead to flow in definitespaced-apart relation to one another and at an acute angle to thesesurfaces to create low pressure zones thereabove.

Accordingly, it is a primary object of the present invention to providean improved chatfer assembly for use in grain separators andcharacterized by its simplicity, ruggedness, effectiveness, and abilityto handle a Wide range of kinds of grain with equal etficiency.

Another object of the invention is the provision of a chatfer assemblyfor grain separators featuring a transversely corrugated surface oneside wall of which corrugations are provided with a row of closelyspaced, large-area openings and the other side of which is imperforatetogether with means for directing generally vertical streams of airupwardly through the openings and spaced from one another to providerelatively quiescent air spaces between adjacent streams through whichgrain gravitates onto the imperforate Walls and through the airopenings.

Another object of the invention is the provision of a chatfer assemblyfeaturing a transversely corrugated surface alternate sides of which areprovided with rows of openings together with adjustable air-deflectormeans therebeneath effective to direct air upwardly through the openingsin thin, generally vertical sheets spaced from one another and out ofwiping contact with imperforate surfaces of the corrugations.

These and other more specific objects will appear upon reading thefollowing specification and claims and upon considering in connectiontherewith the attached drawings to which they relate. I

Referring now to the drawings in which a preferred embodiment of theinvention is illustrated:

FIGURE 1 is a fragmentary longitudinal sectional view through theseparator chamber of a grain separator showing one preferred embodimentof the invention-chatfer assembly in position therein;

FIGURE 2 is a top plan View of the chatfer assembly per se;

FIGURE 3 is a fragmentary bottom plan view on an enlarged scale of theair-deflector adjusting means.

FIGURE 4 is a cross-sectional view on an enlarged scale taken alongbroken line 44 on FIGURE 2;

FIGURE is a smiliar view to FIGURE 4 taken along line 5--5 on FIGURE 2;and

FIGURE 6 is a fragmentary enlarged sectional view taken crosswise ofseveral corrugations of the chaffer assembly under operating conditions.

Referring more particularly to FIGURE 1, there is Shown a preferredembodiment of the invention chaffer assembly, designated generally 10,mounted on a pair of shoes 11 along either interior side of the rear endof grain separator 12. Shoes 11 are suspended from links 13 having theirupper ends pivoted at 14 to the sides of the separator housing. Shoes 11are reciprocated to and fro through a short path by connecting rod 15connected to a drive pin 16 carried by the face of a driven gear 17. Itwil 1 be understood that chaffer asembly 10 is releasably secured toshoes 11 in any well known manner and that a tailings sieve 19 of anysuitable construction bridges the gap between the rear end of chaffer 10and the straw discharge opening 20 at the rear end of separator 12.

Overlying chaffer assembly 10 are a series of conventional straw walkers22, 22 arranged parallel to one another and underlying the main strawpassage along which straw flows to the right as viewed in FIGURE 1.Walkers 22 are mounted on cranks 24 which are rotated to drive alternatewalkers in and out of phase relation whereby the sawteeth on their upperedges cooperate in advancing the straw to the right and out of the rearend of the separator. Grain, chaff and straw escaping between thewalkers falls into space 26 overlying chaffer assembly 10 and tailingssieve 19, the grain being separated out as the straw and chaff continueto the right and out of discharge opening 20.

A fan 27 extending crosswise of the separator draws air in throughopenings 28 at the opposite ends of the fan chamber and directs this airrearwardly and upwardly through assembly 10 and tailings sieve 19. Fullkernels of sound grain fall downwardly through the chaffer assembly intocollecting chamber 30 and are removed by screw conveyor 31. Theunthreshed heads, clusters and imperfect grains collect in chamber 32and are removed therefrom by a screw or anger 33.

Referring now more particularly to FIGURES 2 to 6, there is showndetails of a preferred embodiment of chaffer assembly 10 which includesa rigid perimeter frame 35 and upstanding flanges 36 extending alongitsopposite sides. Suitably secured, as by welding, to main frame 35 is acorrugated sheet metal cover 37 provided with deep corrugationsextending the full width of the chaffer assembly and closed at theirends by flanges 36. The sides of each corrugation-facing rearwardlytoward the straw discharge opening 20 are formed with large-area,closely spaced air openings 38. As is best shown in FIGURE 2, theopenings in one corrugation are staggered or offset laterally relativeto the openings in the next adjacent corrugations. The opposite orforwardly facing sides 39 of each corrugation are imperforate and theirlower edges merge with the lower straight edges of openings 38. Asherein shown, the perforate and imperforate side walls of each groovelie at an angle of approximately 90 degrees to one another and atapproximately 45 degrees to a vertical plane drawn through the bottom ofthe corrugation. However, it will be understood that these angularrelationships are not critical andmay be varied if desired.

It is important that the air from fan 27 be directed to flow generallyvertically through each row of air openings 38 and out of contact withthe imperforate side walls 39 of the corrugations. Simple meansaccomplishing this purpose as herein shown comprises air-deflectingvanes 42 extending crosswise of the underside of the chaffer assemblyand closely adjacent the undersides of each corrugation trough. Vanes 42are supported on shafts 43 journaled in notches opening through theupper edges of retainer strips 44 suitably secured to frame 35. Themidportions of shafts 43 are provided with a crank 45 (FIG- URE 5)seating in the bight portion thereof a rigid operating strip 46. Thisstrip is provided with notches 47 in its lower edge accommodating thebight portion of each crank 45, and, as will be recognized, axialmovement of strip 46 serves to pivot shafts 43 and the individual vanes42 in unison with ons another.

Means for adjusting cranks 45 and thereby the position of the airdeflectors 42 is best shown in FIGURES 3 and 4. This adjusting meansincludes a bracket 48 secured to the common operating strip 46 and'pivotally connected at its lower end to a link 49 by a bolt 50. Therighthand end of link 49, as viewed in FIGURE 3, is connected to the endof the shorter leg of a bell crank 52 pivotally supported on controlsector 55 by a bolt 53. The longer leg of the bell crank projects fromthe rim of sector 55, firmly anchored to frame 35, and serves as anoperating handle for the adjusting means. Sector 55 is formed with anarcuate row of detents 56 frictionally seating a bead 57 formed on theadjacent surface of bell crank 52 and effective to hold the vanes 42 inany desired adjusted position.

The operation of the described grain separating facility for a grainseparator will now be described with particular reference to FIGURES 1and 6. Unthreshed stalks of grain are subjected to thorough beating andbuffeting in forward portions of the grain separator in a manner wellknown in this art. This material then discharges rearwardly onto theforward ends of straw walkers 22 where it is gradually worked to therear along these walkers in a well known manner as grain, chaff and somestraw falls into chamber 26 overlying chaffer assembly 10. There, thestream of material undergoing separation is agitated by a multiplicityof thin sheets of air rising vertically through the parallel rows ofopenings 38. Of importance is the fact that these separate sheet-likestreams of air 60, as illustrated in FIGURES 1 and 6, are separated byintervening zones 61 of relatively quiescent air along which the grain62 gravitates. These quiescent zones 61 overlie the imperforate sidewalls 39 of the chaffer assembly and have a width approximating thedistance between adjacent sheets of air 60.

The above-described rising sheets of air and intervening zones ofrelatively quiescent air are of very considerable importance in thesuccessful operation of a grain separator. Heretofore, it has been thepractice to introduce the air through the chaffer in a directioninclined acutely to the horizontal and directed generally toward therear discharge opening for the straw and chaff. While this arrangementis generally effective in agitating the chaff and straw, adjacent airstreams are in direct contact and flowing transversely of the path offalling grain as well as in direct wiping contact with imperforateportions of the chaffer with the result that grain on or close to thesesurfaces is carried rearwardly and upwardly into the air stream. In thismanner, considerable portions of the grain are carried out of theseparator and lost. According to the present construction and its modeof operation, the rising sheets of air agitate the straw and chaff andkeep it off the chaffer assembly and are separated from one another byan adequate distance for grain to gravitate downwardly onto theimperforate surfaces 39 and thence through openings 38 into thegrain-receiving chambers 30, 32. No air wipes across the imperforatesurfaces 39 but instead the rapidly rising streams of air cooperate withthese surfaces in entrainin'g air from zones 61 thereby to lower the airpressure therein and facilitating the downward passage of the grain.

Air-directing vanes 42 form an important role in the operation of thedescribed assembly, as will be readily understood from FIGURE 6. Thus,these vanes deflect the air passing rearwardly from fan 27 and cause itto rise vertically through openings 38. It is found in practice that theposition of the vanes shown in full lines in FIGURE 6 is highlyeffective and efficient in separating grain of a wide range of sizes andweights, the range of adjustment required under Widely varyingconditions being generally indicated by the dotted line showing of thevanes to either side of the full line position. As will be appreciated,the adjusted position and the width of the air deflectors varies withthe design and arrangement of the adjacent components, the reciprocationspeed at which the chatter is operated, the volume and velocity of theair delivered to the underside of the chatter assembly, and the likefactors readily appreciated by those skilled in this art. The air volumeand velocity can be controlled by any suitable means including thenumber and adjustment of the air-directing vanes 64 in the air plenumchamber, air-control valves for air inlets 28, etc.

It is found that the described chatter assembly is equally etficient andettective in threshing light grains as, for example, alfalfa and clover,as well as the heavier grains such as oats, wheat, rye, barley and thelike. Furthermore, this efliciency is maintained over widely varyingyields, the described chatter assembly having the capability of handlingvery large as well as relatively light and intermediate yields.

While the particular grain separator chatter assembly herein shown anddisclosed in detail is fully capable of attaining the objects andproviding the advantages hereinbefore stated, it is to be understoodthat it is merely illustrative of the presently preferred embodiments ofthe invention and that no limitations are intended to the details ofconstruction or design herein shown other than as defined in theappended claims.

I claim:

1. A chatter assembly adapted to be mounted generally horizontallyacross the rear end of a grain separator for reciprocation in its ownplane lengthwise of the path of the straw, said chatter assembly beingoperable to admit sheet-like vertical streams of air in parallel pathsextending crosswise of straw flowing generally horizontally andrearwardly over the chatter assembly and out the rear end of a grainseparator and effective to agitate and levitate straw and chaff whilepermitting grain to fall in the space between said rising sheet-likestreams of air and to escape through said chatter assembly, said chatterassembly having a generally rectangular frame covered by rigid sheetmaterial corrugated crosswise of the path of straw flow, the oppositesides of said corrugations lying generally at right angles to oneanother with one side facing downstream and the other side facingupstream as respects the direction of straw flow, all the sides of thecorrugations facing downstream having a row of large-area closely spacedopenings each of which rows is ettective to admit a sheet-like generallyvertically disposed stream of air extending from side-to-side of saidchatter assembly, the sides of the corrugations facing upstream beingsubstantially imperforate and being effective to channel grain fallingthereon downwardly through the row of openings immediately upstreamtherefrom, and air deflecting means on the underside of said corrugatedsheet and including means for adjustably supporting the same foradjustment in a range ettective to direct air flowing rearwardly beneathsaid chatter assembly upwardly through each of said rows of openings inparallel generally-vertically-disposed sheet-like streams out of contactwith and lying at an acute angle to the plane of the adjacentimperforate sides of said corrugations, whereby said closely spacedparallel sheet-like streams of rising air are ettective to leviate thestraw flowing rearwardly without imparting substantial downstreamimpetus to the grain and permitting the latter to fall between saidrising air streams onto the imperforate sides of said corrugations andthence through the row of air openings immediately upstream therefrom.

2. A chatter assembly as defined in claim 1 characterized in that saidair deflecting means comprises a plurality of narrow vanes having alength corresponding to the length of said rows of air openings, saidadjustable supporting means including means for pivotally supportingsaid vanes from their upper lateral edges along an axis beneath andclosely adjacent the lower edge of the associated row of air openingsand with the plane of said vanes inclined acutely to the vertical withthe lower edges thereof directeddownwardly and toward the forward edgeof said chatter assembly.

FOREIGN PATENTS 227,083 8 1943 Switzerland.

HARRY B. THORNTON, Primary Examiner.

TIM R. MILES, Examiner.

